Thai repeats a word to change it, and the direction of the change depends on what kind of word it is. In writing the second copy is not written out: it is replaced by the repeat mark ๆ, so ดี ดี appears as ดีๆ.
The instinct is that repetition intensifies. For adjectives it does close to the opposite.
- ดีดีdiː diː
decent; fine; the good sort
written ดีๆ. Vaguer than ดี, not stronger
- ง่ายง่ายŋâːj ŋâːj
easy enough; nothing special about it
Three patterns
On an adjective, repetition softens and generalises: not this exact quality but roughly this sort of thing.
On an adverb of manner, it makes an instruction gentler. ช้า ช้า to a driver is 'take it easy', not 'very slowly'. This is the one you will use daily.
On a noun, it pluralises loosely: not a countable number of them but the kind in general.
- ช้าช้าtɕʰáː tɕʰáː
gently; take it easy
to a driver, a barber, anyone with a blade
- เด็กเด็กdèk dèk
kids; children in general
The one the script cannot show you
There is a genuine intensifying reduplication, and it is marked by pitch: the first copy is said high and long, well above its normal tone, and the second at its ordinary tone. That produces 'gorgeous' rather than 'quite pretty' from the same two syllables.
It is not written and the tone rules do not predict it. This is one of the few places where the spelling does not carry the tone, and it has to be learned by ear. Straightforward intensification, if you want to be safe, is มาก after the word, and it always works.
- สวยสวยsǔːaj sǔːaj
quite pretty, or stunning
which one depends entirely on the pitch of the first copy
- สวยมากsǔːaj mâːk
very beautiful
unambiguous, and never wrong